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Second Schleswig War -

The Second Schleswig War began on February 1, 1864, when Prussian and Austrian troops crossed the border into Schleswig in Southern Jutland in a dispute with Denmark over control of the Duchies of Schleswig.

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The cession of the Duchies of Schleswig -

The war ended on October 30, 1864, with Denmark's cession of the Duchies of Schleswig (except for the island of Ærø, which remained Danish), Holstein, and Saxe-Lauenburg to Prussia and Austria. This painting illustrates the Danish counterattack during the key Battle of Dybbøl on April 18, 1864. Denmark suffered a severe defeat that ultimately decided the outcome of the war.

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Germany's defeat in World War I -

After Germany's defeat in 1918, the Danish government saw an opportunity to take back territory seized by Prussia and Austria during the Second Schleswig War.

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Treaty of Versailles -

In the wake of WWI, Denmark asked the Allied powers at the Versailles Conference of 1919 to include a plebiscite in the disputed Schleswig region. This request was granted, and paved the way for North Schleswig to be returned to Denmark.

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Southern Jutland -

This 1918 Danish map of Southern Jutland shows the region before the plebiscites.

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Allies take control -

Post-war Denmark saw the Allied powers replace German garrisons with a small international force. Pictured are British troops and Danish policemen protecting the train station at then Apenrade in southeastern Jutland in early 1920.

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Security strengthened -

French troops were also stationed in the country as a security force, at places like Haderslev found in the eastern part of Southern Jutland, and other towns.

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National referendums -

In February 1920, national referendums took place to decide the geo-political makeup of a post-war Denmark. Pictured is the commissary-general for the Danish voting areas awaiting the members of the voting committee at the train station in Flensburg, Schleswig-Holstein.

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Three voting zones -

Schleswig was divided into three voting zones—North Schleswig, Central Schleswig, and South Schleswig. Voting rights were given to all adults over 20 who were born in the voting areas, or who had lived there since January 1, 1900.

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Northern Schleswig (Zone I) -

Voting in Zone 1 commenced on February 10, 1920. Turnout was 91.4%. There was a clear majority for Danish affiliation.

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Pro-Danish propaganda -

This pro-Danish propaganda poster reads: "Should we leave this land to a Prussian?"

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The Danish vote -

In Northern Schleswig, there were three Danish votes for every German vote. In Haderslev (pictured), for example, 38.6% of inhabitants voted for remaining part of Germany and 61.4% voted for the cession to Denmark.

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Central Schleswig (Zone II) -

The vote in Central Schleswig took place on March 14, 1920. Turnout was 80.2% in favor of staying German. The poor result in Central Schleswig, particularly in Flensburg (pictured), Schleswig's largest city, triggered Denmark's 1920 Easter Crisis (explained later).

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German propaganda -

This German propaganda poster proclaims: "We have been Schleswigers for 1,000 years. We will remain Schleswigers. That's why we vote for Germany."

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Southern Schleswig (Zone III) -

At the express wish of the Danish government, a plebiscite was not held in the southernmost third of the province as the population was almost exclusively pro-German. Pictured is a late 1920 map of part of northern Europe showing sections of the coasts of Norway, Sweden, Russia, Germany, and Denmark after reunification with Southern Jutland.

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Gradual reunification -

Southern Jutland's incorporation into Denmark was done gradually and carefully. On May 20, Danish currency was introduced in the region. The Danish postal service was also inaugurated on the same day. Pictured: uniformed Danish letter carriers take to their bicycles.

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Reunification Day -

On June 15, 1920, the plebiscite's entire Zone I was transferred to Denmark as the Danish government formally took over the control of Southern Jutland.

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King Christian X crosses the border -

To much fanfare, the law on "The Southern Jutland areas incorporated in Denmark" was signed by King Christian X (pictured) on July 9. German passport and customs controls were officially moved from the river Kongeå to the current border.

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South Jutland is reunited -

The following day, the Danish monarch famously rode his white horse over the demarcated Kongeå frontier to be greeted by jubilant locals in what was now southern Denmark.

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Welcome! -

The occasion was captured by photographers, illustrators, and artists. This painting shows Danish soldiers returning to Northern Schleswig and being welcomed by villagers.

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Easter Crisis of 1920 -

Reunification was not, however, without incident. In light of the results, Prime Minister Carl Theodor Zahle had determined that reunification with Northern Schleswig could go forward, while Central Schleswig would remain under German control. However, many Danish nationalists felt that Central Schleswig should be returned to Denmark regardless of the plebiscite's results.

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Otto Lieb -

King Christian X sided with nationalist sentiment and ordered Zahle to include Central Schleswig in the reunification process. He refused to comply and resigned several days later, after a heated exchange with the monarch. Subsequently, Christian dismissed the rest of the government and replaced it with a de facto conservative caretaker cabinet under Otto Lieb (pictured).

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Michael Pedersen Friis -

The king's actions prompted a constitutional crisis that became known as the Easter Crisis of 1920. Faced with public backlash and the potential overthrow of the Danish crown, Christian backed down and dismissed his own government, installing as a compromise a cabinet under Michael Pedersen Friis (pictured) until elections could be held later that year.

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Denmark's memorial stones -

Visitors to Denmark will very likely come across the memorial stones erected nationwide to commemorate the historic events of February 1920.

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Written in stone -

Around 580 of these stones are dotted around the country.

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Schleswig-Holstein, Germany -

And in Germany, commemorative stones have also been laid as reminders of the historic vote of 1920.

See also: Remembering the April 9, 1940 invasion of Denmark by Nazi Germany

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